Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint/destructiveHint/openWorldHint, and the description confirms "Lecture seule" consistently while adding substantive behavior: the acceptance rules (reach must cover footprint + 2 m, each lift within reach AND load curve by interpolation to jib tip, no overflight of forbidden zones), the default action, and the important caveat that results are indicative and a signed lifting plan is mandatory. It does not describe the shape of the returned verdict, but the safety/validity framing is well disclosed.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the trigger clause, then criteria, then the catalogue, then action semantics, then the disclaimer — a logical order with no redundant sentences. It is dense (one very long clause enumerating the three lift checks), but every element carries information an agent needs.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description still conveys what the tool evaluates and that the answer is indicative, plus the mandatory signed lifting note — enough to call it correctly and interpret the result. A brief note on what the verification returns (per-lift pass/fail vs. a global verdict) would close the remaining gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3; the description adds meaning the schema does not, notably the default value for action and the decision rule behind "choisir" (recommend the smallest crane). The nested scene fields are left entirely to the schema, so the added value is real but limited to one of two parameters.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The opening clause states a specific verb pair and resource: choosing the site crane and verifying its lifts from the model ("choisir la GRUE DE CHANTIER et verifier ses levages depuis la maquette"). No sibling tool in the list covers crane selection or lift verification, and the description's criteria (reach, load curve, forbidden zones) make the scope unmistakable.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

"Appelez quand vous devez choisir la GRUE DE CHANTIER et verifier ses levages" gives an explicit trigger condition, and the action branches ("verifier (defaut, grue declaree dans la scene) | choisir (recommande la plus petite grue)") tell the agent which mode to select and what each does. It does not name an exclusion or an alternative tool, which keeps it just below a 5.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.